Re: GCC 4.0 Ada.Containers Cursor danger.

["Alex R. Mosteo" <devnull@mailinator.com>]

Maxim Reznik wrote:
> Georg Bauhaus wrote:
> 
>>Maxim Reznik wrote:
>>>There are a very few cursors per container in typical program,
>>>so it is not big work.
>>
>>
>>Care to give some data? It is difficult to argue about
>>hot air.
>>
> 
> 
> I look in all my Ada programs. There are a few loops per container,
> no more that 2 or 3 at once. Because cursors's main purpose is
> iteration over containers I think there will be a few cursors per
> container usually.

There are cases where keeping around several (or many) cursors can be 
handy. A need I encountered was to keep a set of elements ordered by two 
different criteria. In my case I wanted to access the objects by "Id" 
and by "Age". Instead of having two copies of each object, or use access 
types, another possible implementation is creating a new container which 
internally uses two maps, one of them containing the objects and the 
other containing cursors for the other set. In this way all dynamic 
memory management is done by the standard containers.